The transportation of fluids such as steam, compressed air, natural gas, and the like, from a centrally located source to remotely located utilization devices is usually carried out at relatively high pressure to minimize pipe size, amount of insulation, etc. For example, a utilization device in the form of a steam drier operates on low-grade steam; and to minimize the cost of transporting steam from a central power plant, high-quality steam (i.e., steam at a relatively high temperature and pressure) is piped to driers at remote locations in a factory where the high-pressure steam is passed through pressure reducers, usually throttling valves, before being applied to the driers. Each pressure reducer reduces the pressure of the steam to a level compatible with the drier, but throttling converts some of the heat in the high-quality steam in kinetic energy which causes "wire-drawing" in the throttling valve and superheats the low-quality steam produced by the throttling. As a consequence of its being superheated, the low-quality steam requires larger heat transfer surfaces than saturated steam.
A conventional approach to minimize such losses is to apply the high-grade steam produced efficiently in a boiler to a steam turbine, whose exhaust supplies the processed steam for the driers. However, this necessitates placing the driers in the immediate vicinity of the turbine to avoid the expense of long runs of relatively large pipe carrying relatively low-quality steam, and to minimize insulation of such pipes. This is not always practical; and for this reason, localized pressure reducers are associated with low-pressure fluid utilization devices in many industrial processes; and this results in a significant waste of the potential of the energy in the steam.
It is therefore an object of the present invention to provide a new and improved localized pressure reducer for use with a high-pressure fluid line in an environment having an electrical grid wherein the pressure reducer does not suffer from the deficiencies of previously known pressure reducers.